The invention relates to a signal processing system with a bus node, which is designed for signal conversion between signals of an internal and an external bus system, and in each case includes at least one interface for coupling to the external bus system and the internal bus system, and with at least one signal conditioning module which is designed for physical conditioning and/or analog-to-digital conversion of signals of an external component and has an interface for the internal bus system and at least one connection for the external component, and is connected to the bus node via the internal bus system. The invention also relates to a method for processing signals in a bus node.
Known from DE 4332895 C1 is a method for fault detection in programmable logic controllers which are built up hierarchically in modular fashion from various electrical components, wherein each component is a physical unit and at least one highest-ranking, higher-level component as designed as control station. Here, the following steps are provided for the procedure: after each installation of at least one component, the module-specific parameters of the respective component are read from a non-volatile memory and checked for compatibility with implemented software modules. Higher-level components are also checked for compatibility with the module-specific parameters of each subordinate component. Any incompatibility found is indicated and subordinate components report the current configuration and each identified incompatibility to the respective higher-level component.
EP 1728131 A2 discloses an electrical field device with a computer-controlled central control module and at least one input/output module with data inputs and/or outputs, wherein the central control module and the input/output module or modules is or are connected via a data bus, and the module parameters giving the type and number of the data inputs and/or outputs of at least one input/output module are made available for retrieval by the central control module. Therefore, the information on the type and number of their data inputs and/or outputs is now already made available by the input/output module or modules.
US 2006/058847 discloses a distributed operating system with integral diagnostic function, a bit bus and a field bus, and includes a field device for generating a field operation characteristic together with a field processing module for processing the field operation characteristic of the field device. The field processing module contains a field diagnostic component and a field communication component, which is designed for communication via the bit bus. The field processing module is designed for the generation of field operating data, including a field diagnostic parameter as a function of the field operating characteristic. An additional processing module is designed for communication with the bit bus and to receive the field operating characteristic. The additional processing module contains an additional diagnostic component and an auxiliary communication component, which includes a field bus interface and a gateway component. The additional processing module is also designed for the generation of additional field data as a function of the field operation data and for transmission of the additional field data via the field bus.
DE 10358231 discloses a device with at least one field connection module for the connection of at least one field device via a first field bus to a higher-level system for data transmission between the first field connection module or modules and the higher-level system, in which the first field connection module or modules has or have a first bus interface connection for connection to the higher-level system via the first field bus and in which the first field connection module or modules has or have a second bus interface connection for connection to a second bus.
US 2002/194547 discloses a method for wiring fault detection, diagnosis and reporting, to test connection devices in a process control system and in particular to determine the electrical properties of a segment protocol bus and the electrical properties of the signals of the protocol transmitted by the bus. In this connection, a signal line of a segment protocol bus is connected to one measuring block out of a multiplicity of measuring blocks within a wiring fault detection unit. The measuring block from the multiplicity of measuring blocks measures an electrical property linked to the segment protocol bus and sends the measured electrical property on a wiring cable to a wiring fault diagnostic manager. The wiring fault diagnostic manager analyses the measured electrical properties to determine the type of wiring fault, and reports the fault type of the wiring fault via a user interface.
The known signal processing systems always include a field device, also described as bus node, which is designed for signal conversion between signals of an internal and an external bus system, together with mostly several modules electrically coupled to the bus node. The modules may be for example input/output modules and/or function modules, in particular a valve module. The electrical coupling between the bus node and the modules may include both electrical power supply to the modules and also an internal bus system designed for bi-directional communication between the modules and the bus node. At the same time, the internal bus system serves on the one hand for the transmission of control signals, which are extracted at the bus node from signals of an external bus system, for example a field bus system, and are converted in the bus protocol of the internal bus system, from the bus node to the modules. On the other hand, the internal bus system is also used for the transmission of signals, for example sensor signals from sensors, which are provided as output signals by the input/output modules, to the bus node. The designation “internal bus system” is also intended to cover bi-directional communication systems, for example in accordance with the I/O link standard, or parallel-wired multi-wire systems, which are also described as multipole systems.